<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>

  <div id="root"></div>

  <script src="../lib/react.js"></script>
  <script src="../lib/react-dom.js"></script>
  <script src="../lib/babel.js"></script>

  <script type="text/babel">
    class App extends React.Component {
      constructor() {
        super()

        this.state = {
          message: 'Hello World'
        }

        this.handleClick = this.handleClick.bind(this)
      }    
      
      handleClick() {
        this.setState({
          message: 'Hello React'
        })
      }

      render() {
        const { message } = this.state
        return (
          <div>
            <h2>{message}</h2>
            <button onClick={this.handleClick}>修改文本</button>
          </div>
        )
      }
    }


    const root = ReactDOM.createRoot(document.querySelector('#root'))
    root.render(<App />)
  </script>
</body>
</html>